examples/rpl_udp/README.md: Replace tabs by spaces

examples/rpl_udp/README.md

@@ -1,7 +1,7 @@
 # Setup the build
 First switch to this application directory:
 
-	cd RIOT/examples/rpl_udp
+    cd RIOT/examples/rpl_udp
 
 The build system provides three specific parameters for the RPL module.
 These parameters are:
@@ -14,23 +14,23 @@ These RPL build parameters and their according _default_ values are used in the
 #### Compiling the executable
 **example for `RPL_MOP_STORING_MODE_MC`:**
 
-	make RPL_MOP=RPL_MOP_STORING_MODE_MC
+    make RPL_MOP=RPL_MOP_STORING_MODE_MC
 
 builds the project and creates `128` entries for the RPL routing table by default.
 
-	make RPL_MOP=RPL_MOP_STORING_MODE_MC RPL_MAX_ROUTING_ENTRIES=103
+    make RPL_MOP=RPL_MOP_STORING_MODE_MC RPL_MAX_ROUTING_ENTRIES=103
 
 builds the project and creates `103` entries for the RPL routing table **overwriting** the default value.
 
 **example for `RPL_MOP_NON_STORING_MODE`:**
 
-	make RPL_MOP=RPL_MOP_NON_STORING_MODE RPL_MAX_ROUTING_ENTRIES=103 RPL_NODE_IS_ROOT=1
+    make RPL_MOP=RPL_MOP_NON_STORING_MODE RPL_MAX_ROUTING_ENTRIES=103 RPL_NODE_IS_ROOT=1
 
 builds the project and creates `103` entries for the RPL routing table for the root node.
 
 #### _[native only]_ Set up a bridge for *two* tap devices for communication
 
-	../../cpu/native/tapsetup.sh create 2
+    ../../cpu/native/tapsetup.sh create 2
 
 The `2` corresponds to the number of _virtual_ nodes to be started.
 The tap devices are bound to the _virtual_ native node on starting the created executable `rpl_udp.elf`.
@@ -38,14 +38,14 @@ The tap devices are bound to the _virtual_ native node on starting the created e
 #### _[native only]_ Starting _virtual_ nodes
 Run the first node
 
-	make term
+    make term
 
 This starts the executable binding a _virtual_ node to the first tap device `tap0`.
 
 **Further nodes must be bound to tap devices manually.**
 For the second node it would be:
 
-	make term PORT=tap1
+    make term PORT=tap1
 
 
 # RPL init
@@ -53,74 +53,74 @@ Type ``help`` to see the commands available.
 
 #### Command order:
 
-	init (r|n|h)
-	server
-	send <node-id> <message>
+    init (r|n|h)
+    server
+    send <node-id> <message>
 
 
 Init your RPL node either as root (`r`), as node router (`n`), or as non-routing node (host-mode) (`h`)
 
-	> init r
-	init r
-	INFO: Initialize as root on address 1
-	6LoWPAN and RPL initialized.
-	Channel set to 10
-	Transport layer initialized
+    > init r
+    init r
+    INFO: Initialize as root on address 1
+    6LoWPAN and RPL initialized.
+    Channel set to 10
+    Transport layer initialized
 
 or
 
-	> init n
-	init n
-	INFO: Initialize as node on address 2
-	6LoWPAN and RPL initialized.
-	Channel set to 10
-	Transport layer initialized
+    > init n
+    init n
+    INFO: Initialize as node on address 2
+    6LoWPAN and RPL initialized.
+    Channel set to 10
+    Transport layer initialized
 
 or
 
-	> init h
-	init h
-	INFO: Initialize as non-routing node on address 3
-	6LoWPAN initialized.
-	Channel set to 10
-	Transport layer initialized
+    > init h
+    init h
+    INFO: Initialize as non-routing node on address 3
+    6LoWPAN initialized.
+    Channel set to 10
+    Transport layer initialized
 
 (It is advised to start all nodes before running the root node, because the interval for sending DIOs from the root increases over time)
 A few seconds withing running, setting and initializing your second node, the nodes will automatically start to exchange control traffic. You should be seeing output similar to the following:
 
-	41 CC FC 34 12 36 12 00 FF FE 00 00 02 36 12 00 FF FE 00 00 01 7A 33 3A 9B 03 F9 90 00 00 04 00 00 80
-	IPv6 datagram received (next header: 3A) from fe80:0000:0000:0000:3612:00ff:fe00:0001 	 ICMP type: 5A 	 ICMP code: 08
-	Received packet from ID 1
-		Length:	34
-		Src:	1
-		Dst:	2
-		LQI:	0
-		RSSI:	0
+    41 CC FC 34 12 36 12 00 FF FE 00 00 02 36 12 00 FF FE 00 00 01 7A 33 3A 9B 03 F9 90 00 00 04 00 00 80
+    IPv6 datagram received (next header: 3A) from fe80:0000:0000:0000:3612:00ff:fe00:0001    ICMP type: 5A   ICMP code: 08
+    Received packet from ID 1
+        Length: 34
+        Src:    1
+        Dst:    2
+        LQI:    0
+        RSSI:   0
 
 You can now use the ``dodag`` command to obtain information on the node's rank in the rpl dodag as well as their preferred parent
 
-	> dodag
-	dodag
-	---------------------------
-	Part of Dodag:
-	fe80:0000:0000:0000:3612:00ff:fe00:0001
-	my rank: 512
-	my preferred parent:
-	fe80:0000:0000:0000:3612:00ff:fe00:0001
-	---------------------------
+    > dodag
+    dodag
+    ---------------------------
+    Part of Dodag:
+    fe80:0000:0000:0000:3612:00ff:fe00:0001
+    my rank: 512
+    my preferred parent:
+    fe80:0000:0000:0000:3612:00ff:fe00:0001
+    ---------------------------
 
 #Sending via UDP
 
 In order to be able to receive UDP messages from other nodes, we have to start `rpl_udp`'s UDP server:
 
-	> server
-	server
-	UDP SERVER ON PORT 511 (THREAD PID: 17)
+    > server
+    server
+    UDP SERVER ON PORT 511 (THREAD PID: 17)
 
 When rpl is running, you can send a message from any participating node to the node initialized as a server (in our case, node 1) using the ``send`` command
 
-	> send 1 hi
-	send 1 hi
-	Successful deliverd 11 bytes over UDP to abcd:0000:0000:0000:3612:00ff:fe00:0001 to 6LoWPAN
+    > send 1 hi
+    send 1 hi
+    Successful deliverd 11 bytes over UDP to abcd:0000:0000:0000:3612:00ff:fe00:0001 to 6LoWPAN
 
 In case of an error message, make sure that rpl is running and you've started the UDP server on the receiving node by running the ``server`` command.